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THEIR DESCRIPTION AND PROOFS OF

surface, with but occasional breaks of continuity, where the rain had washed illuvium transversely and filled it, or where the ground had been tilled between the olives, for more than a quarter of a mile. I was informed by the same soldier (whose testimony I had thus proved trustworthy) that he had himself traced the fissure F for nearly two Italian miles in a west and south-west direction, which was one generally coinciding with the horizontal contour along the slope of the hill side. Returning back to whence we started, I found two divergent fissures (as figured), and traced one of these in a S. W. and S. direction for some hundreds of feet, down through the olive orchards parallel to the road up to Auletta. The one from h to k led me to try to follow it in a contour line, along the S. W. slope of the town, and without much difficulty I found it again, where the earth got deeper, and traced at several points, but not continuously (much matter having been washed across it on this steep slope), the fissure . It was a similar little trench to the former, but as in Fig. (a, 132), one side of the greatly higher than the other, smaller in size, and harder to trace than the preceding from the want of surface vegetation and the pebbles rolled into it. In all these it was manifest, that the fissure was the evidence of a great earth slip, and had resulted, not from any direct rending asunder of the ground or rocks beneath it, but that the clay masses had when shaken violently upon the inclined beds of rock upon which they were superposed, slid down bodily by gravity, and parted off from each other at these fissures.

The fissures, by their direction, perfectly sustain this view, but are absolutely opposed to the idea of fracture, either by shock or by unequal or local sudden elevation or